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Successful application of electrocoagulation technology requires a thorough evaluation of electrode behaviour. This study is concerned with the treatment of fermentation wastewater, generated by molasses-fed biorefineries in large volumes and containing high concentrations of biorecalcitrant, coloured organic melanoidins that form a highly dispersed colloid. The polarisation behaviour, surface morphology and current efficiency of both hot rolled coil steel and 5005 aluminium electrodes were investigated. The steel electrodes were found to be susceptible to aggressive anodic pitting which is attributed to the high chloride content of the wastewater, while the aluminium exhibited anomalous corrosion of the anode and cathode. The redox potential of the wastewater has a significant effect on Fe 2? /Fe 3? speciation with steel electrodes and thus on the decolourising efficiency of electrocoagulation. The practical implications of the corrosion characteristics are discussed.

The impact of electrode corrosion behaviour, reactor geometry and current density on electrocoagulation efficiency were investigated for the treatment of molasses process wastewater. Two laboratory-scale vertical plate electrocoagulation reactors were used for this investigation: the first being a low aspect ratio bath reactor with a low specific electrode area, while the other was a high aspect ratio column reactor with a high specific electrode area. Anomalous anodic dissolution and cathodic corrosion of the aluminium electrodes both contributed significantly to overall metal consumption. Increasing specific electrode area and aspect ratio each led to improved treatment efficiency, whereas the impact of current density was more complicated involving the combined influences of several competing effects. The space-time yields of coagulant and bubbles (both functions of specific electrode area, current density and current efficiency) were found to influence mixing within the reactor and thus treatment efficiency.

The Humber region, in North East England, is a major hub of industrial activity and trade. It has seen applications of industrial symbiosis for many years, initially centred on 'top-down' infrastructure projects with large capital investment but subsequently following a 'bottom-up' approach engaging industries in the area. Reductions in GHG emissions and waste generation have already been impressive. The possibilities for further savings, recognising the European Union's aspirations for deep GHG cuts and the objectives of the A.SPIRE partnership involving 114 stakeholders from the process industries in Europe, have been explored in the LOCIMAP (low-carbon industrial manufacturing parks) project, which involved partners from across Europe. Industrial symbiosis has been central in the plans for LOCIMAP from the outset. Studies conducted for LOCIMAP have revealed that more substantial savings require industrial symbiosis to be designed in, rather than developed once facilities exist. Major further savings depend on co-location of activities in eco-industrial parks to enable systematic process integration, but following this approach raises further questions, including:-How can such systems be engineered without compromising safety? -What are the implications for system resilience? -How does close integration affect operations such as maintenance?The project has shown that we have the engineering ability to achieve deep reductions in energy use and GHG emissions provided industries can be located in eco-industrial parks with interactions designed according to thermodynamic principles. Barriers to realising this concept, to achieve a new industrial revolution, include an economic and fi scal system which means that design for optimal economic performance leads to different outcomes from designing for optimal environmental performance.